Animal models of fatigue in major depressive disorder

Relationship between subjective and objective fatigue and sleep characteristics in individuals with anxiety and mood disorders: An exploratory study

OBJECTIVE

Fatigue and sleep disturbances are important symptoms of anxiety and mood disorders (AMD). Studies about the relationship between these variables usually rely on self-report assessments. Therefore, the aim of our exploratory study was to investigate the independent correlations between subjective and objective fatigue and sleep characteristics in individuals with AMD.

METHODS

In sum, 233 individuals with AMD attending a stress-related disorders day care unit (78.5 % females, mean age 39.0 years old) participated in a cross-sectional study. Participants completed the Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, Multidimensional Fatigue Inventory-20, and Pittsburgh Sleep Quality Index self-report questionnaires, as well as an exercise capacity workload test for assessing objective fatigue and polysomnography monitoring for evaluation of sleep structure.

RESULTS

In individuals with AMD, exercise capacity workload was associated with lower percent of stage 1 sleep (β = - 0.17, p = 0.006), REM latency (β = -0.13, p = 0.042), and wake after sleep onset (β = -0.12, p = 0.039). General fatigue was associated with a higher percent of body movements (β = 0.12, p = 0.047), as well as mental fatigue was associated with a higher percent of body movements (β = 0.13, p = 0.029), and a higher score on the PSQI (β = 0.21, p = 0.002).

CONCLUSIONS

Objective sleep characteristics were associated with objective assessment of fatigue, while subjective sleep quality was associated with subjectively assessed mental fatigue.

Behavioral and dopamine transporter binding properties of the modafinil analog (S, S)-CE-158: reversal of the motivational effects of tetrabenazine and enhancement of progressive ratio responding

RATIONALE

Atypical dopamine (DA) transport blockers such as modafinil and its analogs may be useful for treating motivational symptoms of depression and other disorders. Previous research has shown that the DA depleting agent tetrabenazine can reliably induce motivational deficits in rats, as evidenced by a shift towards a low-effort bias in effort-based choice tasks. This is consistent with human studies showing that people with major depression show a bias towards low-effort activities.

OBJECTIVES

Recent studies demonstrated that the atypical DA transport (DAT) inhibitor (S)-CE-123 reversed tetrabenazine-induced motivational deficits, increased progressive ratio (PROG) lever pressing, and increased extracellular DA in the nucleus accumbens. In the present studies, a recently synthesized modafinil analog, (S, S)-CE-158, was assessed in a series of neurochemical and behavioral studies in rats.

RESULTS

(S, S)-CE-158 demonstrated the ability to reverse the effort-related effects of tetrabenazine and increase selection of high-effort PROG lever pressing in rats tested on PROG/chow feeding choice task. (S, S)-CE-158 showed a high selectivity for inhibiting DAT compared with other monoamine transporters, and systemic administration of (S, S)-CE-158 increased extracellular DA in the nucleus accumbens during the behaviorally active time course, which is consistent with the effects of (S)-CE-123 and other DAT inhibitors that enhance high-effort responding.

CONCLUSIONS

These studies provide an initial neurochemical characterization of a novel atypical DAT inhibitor, and demonstrate that this compound is active in models of effort-related choice. This research could contribute to the development of novel compounds for the treatment of motivational dysfunctions in humans.

The start of gastrectomy at different time-of-day influences postoperative outcomes

Gastric cancer (GC) continues to be 1 of the malignant tumors with high morbidity and mortality worldwide. Although the improvements in targeted inhibitor therapy have promoted survival, the first choice for GC patients is still surgery. However, prolonged surgery may tire surgeons and affect surgical outcomes.To detect whether different time-of-day radical gastrectomy influenced short-term and long-term surgical outcomes.This study included 117 patients between 2008 and 2012 who underwent a radical gastrectomy. These patients were grouped into the morning (before 13:00) and afternoon (after 13:00) groups or divided into 2 groups according to the median operation start time (before or after 11:23). Then, the relevant influence of the surgical start time was analyzed.The morning group (before 13:00) and the front median group (before 11:23) showed longer operative time (P = .008 and P = .016, respectively), lower estimated blood loss (P < .001 and P = .158, respectively), and longer time before resuming oral intake (P < .001 and P < .173, respectively) than the afternoon group (after 13:00) or latter median group (after 11:23). Starting the operation in the morning had no effect on the rate of postoperative complications. The operation start time had no significant influence on the overall survival of patients who underwent a radical gastrectomy. However, in subgroup analysis, patients who underwent a distal gastrectomy faced poor prognosis when their surgery started after 13:00 (P = .030).The results suggest that the operation start time might be an indicator of total operative time, estimated blood loss, and the time to resuming oral intake. The operation start time may also influence the prognosis of radical gastrectomy in patients with GC.

Mapping the Alterations of Glutamate Using Glu-Weighted CEST MRI in a Rat Model of Fatigue

Objective: Glutamate dysregulation may play an important role in the pathophysiology of fatigue. Glutamate weighted chemical exchange saturation transfer (Glu-weighted CEST) MRI is a recently developed technology which enables measuring glutamate in vivo with high sensitivity and spatial resolution. The purpose of this study is to map the alternations of brain glutamate in a rat model of fatigue. Methods: Rats were subjected to 10 days fatigue loading procedure (fatigue group) or reared without any fatigue loading (control group). Spontaneous activities of rats in the fatigue group were recorded from 3 days before fatigue loading to 4 days after the end of fatigue loading. Glu-weighted CEST were performed following 10-day fatigue loading. Results: Rats in the fatigue group exhibited significant reduced spontaneous activities after 10-day fatigue loading. The glutamate level in the whole brain increased significantly in the fatigue group compared to that in the control group. Further analysis of glutamate in the sub-regions of brain including the prefrontal cortex, hippocampus, and striatum revealed a trend of increment, although statistical significance was not reached. Significance: The increase of glutamate level in the brain may be a crucial process involved in the pathophysiology of fatigue.

State-of-the-Art Internet of Things in Protected Agriculture

The Internet of Things (IoT) has tremendous success in health care, smart city, industrial production and so on. Protected agriculture is one of the fields which has broad application prospects of IoT. Protected agriculture is a mode of highly efficient development of modern agriculture that uses artificial techniques to change climatic factors such as temperature, to create environmental conditions suitable for the growth of animals and plants. This review aims to gain insight into the state-of-the-art of IoT applications in protected agriculture and to identify the system structure and key technologies. Therefore, we completed a systematic literature review of IoT research and deployments in protected agriculture over the past 10 years and evaluated the contributions made by different academicians and organizations. Selected references were clustered into three application domains corresponding to plant management, animal farming and food/agricultural product supply traceability. Furthermore, we discussed the challenges along with future research prospects, to help new researchers of this domain understand the current research progress of IoT in protected agriculture and to propose more novel and innovative ideas in the future.